Diathermic apparatus



April 17, 1928'.

G GROSSMANN DI'ATHERMIC APPARATUS Filed Oct. 7. 1927 flat X7 TraeMa-rsPatented Apr. 17; 1928.

UNITED STATES GUSTAV GBOSSMANN, OF BERLIN, GERMANY.

DIATHERMIC APPARATUS.

Application filed October 7, 1927, Serial no. 224,569, and in GermanyNovember 23, 19 26.

This invention relates to improvements in apparatus employed fordiathermic treatments, and has particular reference to electrode heatingmeans therefor.

It is desirable to heat the electrodes that are to be used fordiathermic treatments before they are laid upon the body of the patient.

i In accordance with the present invention this heating isefi'ected-b'yuneans of ballast resistances or ballast lamps that arbuilt into" the'diathermic apparatus and which are employed, as is wellknown, for'the protection of the oscillatory circuits, and particularly'15 of the spark gap, from injuriousheating in case of only a slightemployment of the energy or a total non-use thereof. For this purposethe resistances are built-in in the vicinity of one part at the wall ofthe ap- 20 paratus. For the purpose of receiving the electrodes a niche,tunnel "or a pipe, on the walls of which the ballast resistances are ar1 ranged, may be provided in the casing, or, more simply, a certainportion of the cover 26 of the casing which is suitable for the 'placingof the electrodes thereon may .be used for heating the latter.

One form of the invention is represented in the drawing, wherein thefigure is a perspective view of the apparatus. I

All parts of the diathermic apparatus, with the exception of themeasuring device and the connection terminals, arehoused in the box-likecasing is, The cover of this casing is provided with perforations d attwo 1 passes to. said electrodes places,-that is, on opposite sides ofthe measuring device m. Directly below these perforations, the ballastresistances w are built in, asis shown on the one side where the coveris partly broken away for purposes of illus- 4o tration. These ballastresistances may consist of insulating plates which are wound with aribbon or wire of resistance metal.

The treatment electrbde's to be heated are laid upon the. perforatedportions of the cover. The air that is heated by the ballast resistancesthen rises through the perforations from the interior of the casing andheats the electrodes.

What is claimed is: I ii 1. In a. diathermic apparatus, a casing, andballast resistances in said casing for the protection of the oscillatorycircuit of the" apparatus arranged in the vicinity of one wall of saidcasing in such manner that the electrodes of the apparatus which areplaced in said vicinity are heated by said resist- 2. Apparatus inaccordance with claim 1 characterized by said wall being provided -withperforations through which the heat passes to said electrodes.

3. Apparatus in accordance with claim 1, characterized by said wall"being provided with perforations through wlficlrthe heat and saidresistances being built inthe casing directly beneath the cover thereof.

Y GUSTA GROSSMANN,

